Motion picture apparatus



April 30, 1935.

L. GROSS MOTION PICTURE APPARATUS Filed March 24, 1932 2 Sheets-Sheet 1April 30, 1935. L. GROSS 1,999,634

MOTION PICTURE APPARATUS I Filed March 24, 1932 2 SheetsSheet 2 PatentedApr. 30, 1935 4 UNITED STATES PATENT OFFICE Louis Grel, husanne',Switserland Application m :4, m2. Serial He. seems In Switserland April2, 1m

SCIaima (01-88-101) This invention relates to motion pictureaprepresentation of a film carrying a sound record paratus and moreparticularly to means for proobtained according to the presentinvention. ducing a synchronized accompaniment to the pro- In Figure 1,the projecting apparatus I is projection of a film in accordance withthe variations vided with two objectives 2 and I. The objective 5 ofintensity and movement of the light on the 2 projects the pictures of afilm 1'' as usual on 5 screen. I the screen 4 which is ior examplesituated in a Cinematography may be considered an art the moving pictureshow room, while the objective 3 means of expression thereof being themovement of relative great angular aperture projects the which isrendered perceptible by images which pictures on a screen 8 situated inthe cabin of the 10 may vary in shape, position and luminosity.operator. This screen I is constituted by juxta- 10 The projectingdevices which are used in this art position of a great number ofphoto-electric cells. are noisy and for thisreason it has become theEach of these cells is electrically connected to use to accompany theprojection of a him by one or several succeeding relays. Thelast one ofmusic to cover the noise of the projecting apsuch succeeding relays canbe arranged to have paratus. Music however has its own rhythm and amechanical action for producing sound either 15 signification and hasthe effect to introduce a directly by operating sound apparatus orindidisturbance into the impressions of the spectator. rectiy by actingon the operating members of a It is possible to conceive an art ofmovement of known musical instrument. For example there which the meansof expression would be reinmay be provided as many nnal relays as thereforced by a production of perceivable phenomena are keys or utilizednotes of one or several musical which are exactly synchronized with thefiuctuainstruments such as pianos, organs or others. tions of the imageprojected on the screen. In Figure 1 it is seen that the various'photo-The present invention has as its object the electric cells I may beconnected to the relays provision of an accompaniment to the projectionby means of a plug-switchboard I permitting to of moving plctures'as setforth above by the provary the connections between the cells and the g5duction of acoustical, visual or other phenomenarelays, that is to sayto connect any particular These phenomena may be of a physicallydefincell with any particular relay or group of relays able charactersuch as intensity of sound, its and thus with any particular soundproducing pitch and its timbre or stamp, or as color or meansconnectedto the terminals I of the switch "0' intensity of light. Suchcharacters may vary for board 0. so each particular film or given partof a film ac- As shown in Figure 2, this switchboard can cording toarbitrary but fixed laws by means of be placed in the line leading awayfrom the last which laws these characters are made dependent relay.Inthis figure there have been represented on the position of illuminatedpoints and of the one of the cells I, a'source of electricity 0, a firstinstantaneous degree of illumination of such relay It acting on thearmature II to close the 35 points. circuit of an electromagnet llhaving a movable My invention will be clearly described hereincore IIand connected to a source of electricity after, reference being had tothe accompanying H. The core It is subjected to the action of drawingsin which, a retracting spring and can for example con- 40 Figure 1 ageneral diagrammatic view 0! an trol the-admission of air into an organpipe it 40 apparatus for carrying out the invention;. by operating thevalve II. Figure 2 shows also Figin-e2showsaseriesofrelaysconneetedtothstthelastrelaycanactdirectlybymeansof mechanical operating devices; anelectromagnet II on one of the keys I I o! a Figure 3 shows a of theapparatus comkeyboard of a piano, organ or like instrument.

4 prising a relay tube with three electrodes; The Figure 3 shows a partof the installation FiguressJsnd'oshoweachaportionoftheinwhichacell'lisconnectedtothesoundproapparatus in which photo-electriccells are disducing apparatus by the intermediary of a relay posedinvarious, manners; constituted by an amplifying tube ll having Figure '1isa diagram showing partially the three electrodes and to the grid 20 ofwhich-the connections of a series of photo-electric cells .cell'isconnected. The electromagnet 2| can act with sound producing apparatus;upon any musical instrument and the electro- Figure] showsacomplementary device which magnet 22 with its armature 28 can operatemay be added to that shown in Figure l and sound devices such as a bell24. destined for phono-photographic recording. The case where the relaywill be constituted Figures 9 and 10 show each a diagrammaticbytheelectrontube ll'isheredescribedasparticularly applicable to theembodiment of an installation comprising a recording device asrepresented in Figure 8 and the same is the case for the embodimentsaccording to Figs. 4 to 7, but the devices shown in these figures arealso applicable to the general form of an installation comprising norecording means.

Figures 4, 5 and 6 show three screens I on the surfaces of which aredisposed the photo-electric cells. These cells 'i may be arranged instraight lines 26, or in concentric circles 25 which may be equidistantas shown in Figure 4 or may be nearer to each other towards the centeras'are the circles 21 in Fig. 5. The cells I are disposed on thesecircles in such a way that their number in proportion to the surface isincreased towards the center of the screen, as the greatest attractionfor the spectator will usually be in the center of the picture.

In Figure 7 a screen of photo-electric cells has been represented inwhich the cells are disposed according to concentric rectangles. It hasbeen shown how the cells of one group can be connected each to anelectron tube relay is, i8, i9" and to oscillating circuits 2!, 29',2!", and together to an amplifier 30 connected to a telephonic receiveror loud speaker II.

The loud speaker can be connected to several separate amplifiers 30 ofwhich the amplifying capacity is more powerful the nearer thecorresponding group of photo-electric cells is disposed towards thecenter of the screen, so that a prevailing effect is given to themovement of the picture adjacent the center of the screen.

In Figure 8, a microphone II is made to vibrate by the action of thenoise or sound accompaniment of a film as F in Fig. l which is projectedon a screen I constituted by photo-electric cells. This device shown inFig. 8 is destined to produce a permanent record of the soundaccompaniment of a film. The microphone ll is connected by one orseveral electron tubes 32 to a galvanometer 33 having a mirror N ofwhich the deflection is proportional to the intensity of the current. Asource of light 35 illuminates the mirror which sends a light beam to afilm f moving pe pendicularly to the plane of the figure. when the filmis developed it carries a sound record which may be reproduced in theordinary manner. This film may be then associated with the picture filmF and copies can be made of both films separately or while they areunited. It is therefore possible that all existing installations for theprojecting of sound films can reproduce thesecompaniment oi' the film Frecorded on the film ,f.

The mirror 34 of the galvanometer 33 may be replaced by a speculardiaphragm which is made to vibrate directly by the sound or noise whichis to be recorded.

It follows from the foregoing that the invention may be used for twodifferent purposes. According to the first use of the invention, a soundaccompaniment of a film can be obtained without adding anything to ausual silent film. But in this case it is necessary that each theatre inwhich a film is shown and when such an accompaniment is desired, beequipped with an installation comprising the elements shown in Figures 1and 2 or,-1, 4 to 7. The screen I carrying the photo-electric cells maybe placed also immediately behind the ordinary projection screen 4.

In order to prepare a film for projection withan accompaniment accordingto the invention,

thefilmwillbeproiectedonthescreensland 5 and the picture as well as theproduced sound will be watched. The connections of the switch board iwill then be made, and changed when necessary,-so that the soundproduced by the instrument to which the cells are connected is not theresult of a mixture of any sounds capable of being emitted, but gives acompound of harmonic and agreeable tones'or sounds.

These may be for example succeeding perfect maior or minor chords ofwhich certain tones prevail over others when a given place on the screenreceives more light and other places receive less light. When a relay inthe form of an electron tube is used, the sound produced by each cell ofthe screen can have an intensity which is proportional to the luminousflux acting on the cell. When once the desired adjustment of theconnections on the switchboard I has been achieved, the film can beprojected any number of times and always the same sound efiects will beobtained. In the case of an installation according to Fig. 1, such anadjustment must be made however for each diiferent projectinginstallation. It is therefore an advantage to use the sound recordingdevice according to Fig. 8 so that the setting of the switchboard has tobe made once only for one film. The invention is not limited to theproduction of an acoustical accompaniment for the projecting of films;the action of the screen of photo-electric cells could be used also toproduce light eii'ects, for example to diffuse colored lights in thofilm show room of which the color could vary with the fluctuations v ofthe pictures.

Figures 9 and 10 show each; sound record obtained with a deviceaccording to 8 for two particular cases of picture films. Figure-9 thepicture film 36 is supposed to be composed of successive images of whichthe mean transparency is invariable and which represent moving objectsdiagrammatically represented by black lines 4|. In this case the soundrecord]? obtained according to the described method from the picturefilm 3i and which will be placed on the space 30 reserved for thispurpose on the picture film, is provided with portions 0', b. c, d, of alength corresponding to the length of successive images a, b, c, if,each length of the sound record varying from its succeeding length inaccordance with the variations of the movable objects on thecorresponding images. The movement of the represented black lines withrespect to the photo-electric cells receiving i ht across the filmproduces a change in the sound emitted by'the sound producinginstruments controlled by the cells. These changes appear in the soundrecord 31 as variations of the tone and of the frequency only when it issupposed that all sound producing instruments are so adjusted that theyproduce sounds of equal intensity (amplitude of the oscillations) andwhen it is further supposed that the movements of the black lines aresuch that the photo-electric cells are either fully illuminated orentirely dark. The sound record 31 represents therefore oscillations ofconstant amplitude. It will be understood that the represented case issimplified in reality the sound record will contain variations of toneand variations of intensity and frequency.

to the extreme and that l 1,m,sas method from the picture iilm llcomprises lengthsv a, b, c, d 'otwhich the mean transparency variesaccording to the mean transparency of thecorresponding images a, b, c,d. with the diagrammatic representation or the sound record in Fig. 10it will in reality be the amplitude of the oscillations oi the sinuousline representing the recordwhich will be proportionate to the meantransparency. The sound record has been shown secured to the picture himwith a certain displacement between the images 0! the film and thecorresponding lengths of sound record to take care of the diflerence inthe speed of gation of sound waves and light waves and or the distancebetween the two objectives 2 3 or the projection apparatus shown in Fig.

I claim:

1. Motion picture apparatus comprising a picture screen, a sound screenincluding a plurality of photo-electric cells disposed over the surfaceoi the screen, electric circuits including said photo-electriccells,-projecting means for simultaneously projecting the pictures of apicture film on said picture screen and on said sound screen, soundproducing instruments, and electrically operated means included in saidcircuits for actuating the sound producing instruments upon saidphoto-electric cells closing said circuits.

2. Motion picture apparatus comprising a picture screen, a sound screenincluding a plurality of photo-electric cells disposed over the area ofthe screen, a picture film projection machine including two objectives,means for moving a picture film in front or both objectives forsimultaneously projecting the pictures of the-film on the picture screenand on the sound screen, sound producing instruments, electricallyoperated means for actuating said sound producing instruments, andelectric circuits including said photoelectric cells and saidelectrically operated means whereby said sound producing instruments areoperated upon the photo-electric cells closing said circuits.

3. The method of producing a combined sound and picture film, whichcomprises projecting a beam of light across a moving picture iilmo'n ascreen formed of a plurality of photo-electric cells, inter-posing eachphoto-electric cell in an electric circuit whereby the circuit will becontrolled by the light falling across the picture illm on said cell,including electrically operated actuating means for sound producinginstruments in said circuits whereby variations in translucency at acertain point of the moving picture iilm will produce correspondingvariations in the electric circuit controlled by the light traversingsaid point of the picture film, photographically recording the soundproduced by said sound producing instruments upon projection of the iilmon said screen, and then associating the photographic sound record withsaid picture illm.

4. The method of producing a combined sound and picture film, whichcomprises projecting a beam oi light across a moving picture rllm on ascreen formed of a plurality of groups of electrically interconnectedphotoelectric cells, including each group of interconnected cells in anelectric circuit whereby said circuit will be influenced bythe' lightfalling across the picture film on the photo-electric cells included insaid circuit, including electrically operated actuating means for soundproducing. instruments in each circuit whereby variationsin'translucency or a certain point of the picture illm will producecorresponding variations in the electric circuit influenced by the lighttraversing said point of the picture film, photographically recordingthe sound produced by said. sound producing instruments upon projectionof the picture iilm on said screen. and then associating thephotographic sound record with the picture film. a.

5. A combined sound and motion picture rllm comprising a plurality ofsuccessive images representing picture scenes, and -a photographic soundrecord, said sound record comprising portions 0! a length equal to thelength of each individual image of the picture him, the characteristicsof the successive portions of the sound record varying in accordancewith the variations in translucency and with the variations in therepartition of light and dark zones of the corresponding successiveimages oi the picture illm.

LOUIS GROSS.

